Question

I need help with translating some code from VB to C#.

Public Function ToBase36(ByVal IBase36 As Double) As String
    Dim Base36() As String = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"}
    Dim v As String
    Dim i As Decimal
    Do Until IBase36 < 1
        i = IBase36 Mod 36
        v = Base36(i) & v
        IBase36 = Math.DivRem(Long.Parse(IBase36), 36, Nothing)
    Loop
    Return v

End Function

My problem is how type conversion works in VB, and this line gives me most trouble since IBase36 is a double, Math.DivRem() in this case should return long and Long.Parse() need string.

IBase36 = Math.DivRem(Long.Parse(IBase36), 36, Nothing)

Here is my translated, working code thanks to the JaredPar and others

    public static string ToBase36(double IBase36)
    {
        string[] Base36 = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z" };
        string v = null;
        long i = default(long);
        while (!(IBase36 < 1))
        {
            IBase36 = Convert.ToDouble(Math.DivRem(Convert.ToInt64(IBase36), 36, out i));
            v = Base36[i] + v;
        }
        return v;
    }

Answer 1

To translate it’s important to understand first how the VB.Net code functions. Under the hood it will essentially generate the following

Dim unused As Long
IBase36 = CDbl(Math.DivRem(Long.Parse(CStr(IBase36)), 36, unused)

Note: The unused variable is necessary because the third argument is an out. This is an important difference when translating to C#.

The most natural C# equivalent of the above is

long unused;
IBase36 = Convert.ToDouble(Math.DivRem(Long.Parse(IBase36.ToString()), 36, out unused);